texture to scale on object
Well exporting textures is going to be an issue but I'll assume here you will only require exporting UV coordinates.

This would be trivial to accomplish using any type of automated texture coordinates like Generated or Object, however, to be able to export texture coordinates you will most likely be required to unwrap your mesh and create a UV map, unwrapping doesn't translate well into scene referred units, since unwrapping will more often than not introduce distortions.

The way I see it you have two options, both involving third party addons.

Either use World Scale UV or Magic UV addon.

What they both do is try to unwrap your mesh in such way that it approximates texture size to a defined scene dimention.